[WindowDecor] Force set layoutDirection in ReusableWindowDecorViewHost

Recall: http://recall/clips/13edbfbb-2115-41f9-8f4a-e720bb6bf4fb

This is a quick fix for the bug where app headers don't switch to the
correct RTL layout when system language is updated. This affects both
tasks that are already open and newly launched tasks, but seem to only
affect WindowDecors acquired from the pool in
PooledWindowDecorViewHostSupplier.

The real culprit could be a bug in Core where ViewRootImpl is not
resolving Rtl properties even though the configuration has changed. This
CL is a quick patch to resolve the issue affecting app headers.

Bug: 414495875
Test: Manual; change system language to a RTL language while tasks are
open. Observe that open tasks and newly launched tasks have the correct
RTL layout
Flag: EXEMPT bugfix

Change-Id: I87460f0cf583ecd8cee3f0b2728c534bca90185d